Improvement of Signal to Noise Ratio for Quartz Crystal Microbalance with Viscous Damping
説明
Our study introduces Vector Network Analyzer as a method to obtain resonance frequency. Acoustic loading on a QCM result in admittance change, which can be detected by Vector Network Analyzer. The feasibility of SNR improvement was confirmed by the QCM in contact with glycerol-water solution with various concentrations. The resonance frequency can be determined by reading the maximum conductance frequency using motional admittance method. Since viscous damping causes high noise level, we introduced a curve fitting method by utilizing all data points within the certain frequency range to obtain resonance frequency. Then we applied Savitzky-Golay filter, with polynomial approximation within the moving window to further smoothen the frequency data, keeping its sharp response. Savitzky-Golay filter was found to be able to suppress noise within the windows size of 41, without further improvement in bigger windows size. However, a window size of 7 was considered adequate, confirmed by paired t-test.
収録刊行物
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- 2018 IEEE International Ultrasonics Symposium (IUS)
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2018 IEEE International Ultrasonics Symposium (IUS) 1-9, 2018-10-01
IEEE